This invention relates to systems and methods for plugging a pipeline under pressure. “Pipeline” as used hereinafter is inclusive of any tubular member made of metal for carrying fluid (liquids or gases). Whereas U.S. Pat. No. 7,270,139 is particularly useful for controlling flow of high temperature liquids or gases, the present invention can be used for either ambient or high temperature applications. The composition of the elastomeric seals determines the range of the applicable temperature. However, the ferrule design may be used at elevated as well as ambient temperatures.
Tools or machines for tapping or for closing fluid flow therethrough include the following:
PAT. NO.INVENTORTITLE3,614,252Rose et al.Tapping Apparatus4,579,484SullivanUnder Water Tapping Machine4,880,028Osburn et al.Completion Machines5,439,331Andrew et al.High Pressure Tapping Apparatus5,612,499Andrew et al.Method of Inserting A Sensor Into APipeline6,012,878HicksPressure Balanced Subsea Tapping Machine7,270,139Calkins et al.Cam-Assisted, Wedge Actuated, Metal-to-Metal Seal, Block and Bleed Plugging Tool
Tapping machines, such as the kind described in the above-mentioned U.S. patents, are for tapping a hole in a pipeline while liquids or gases are flowing through them, that is, while the pipeline is under pressure. Tapping procedures of this type are customarily carried out primarily for one of two purposes, that is, to provide a branch fitting on the pipeline or to enable fluid flow through the pipeline to be blocked. Other examples of prior art that describe and illustrate plugging the interior of a pipe include the following U.S. Pat. Nos.:
PAT. NO.INVENTORTITLE3,170,226AllanLine Stopping and Valve InsertingApparatus and Method3,599,663Ver NooyHot Tapping Apparatus3,626,475HicksHigh Temperature Pipe-PluggingApparatus3,665,966Ver NooyPipe Plugger3,785,041SmithMethod For Plugging Pipe3,872,880Ver Nooy et al.Plugging Apparatus4,411,459Ver NooyBranch Fitting for Providing Access tothe Interior of a Pipe5,443,095Glossop, Jr.Fluid Blocking Device5,531,250Freeman et al.Device for Plugging the Interior of aPipe7,270,139Calkins et al.Cam-Assisted, Wedge Actuated,Metal-to-Metal Seal, Block and BleedPlugging ToolGB1,064,398Pass and Co.Pipe Line PluggerLtd.